Management strategy in actinomycosis brain abscess.

We reported herein a case of isolated cerebral actinomycosis in a 54-year-old immunocompetent man. Brain MRI showed a left frontal intra-axial lesion and perilesional edema. We performed an open biopsy of the left frontal enhancing lesion. Intraoperative findings showed a yellowish, malleable, and capsulated lesion that was well defined with surrounding normal tissue within pus inside and lacked any necrotic content. MR spectroscopy showed a high level of choline, lactate, and lipid peaks with a choline/N-Acetylaspartic acid ratio of 1.8. The diagnosis was confirmed histologically, and the patient was treated successfully for 3 months after surgical aspiration. Surgical management allowed to confirm the diagnosis with a shorten antibiotics, a rapid resolution of symptoms, and a complete recovery.

Utility of the cytological criteria in the diagnosis of malignant pleural mesothelioma: Making the bridge between theory and practice.

INTRODUCTION: The diagnosis of malignant pleural mesothelioma (MPM) depends on microscopic examination performed on pleural biopsies taken under thoracoscopy. However, it has recently been established that cytology presents a significant diagnostic contribution enabling an earlier diagnosis with a minimally invasive procedure. AIM: To assess the diagnostic value of consensual cytological features of MPM in the differentiation between adenocarcinoma, mesothelioma and reactive mesothelial cells in pleural liquid. METHODS: All available retrospective records from the computerized pathology database system and pathology reports were searched for malignant pleural effusion cytology specimens, over a 5-year period from January 2015 to February 2020. The cytological criteria based on the international Guidelines for cytopathologic diagnosis of epithelioid and mixed type of MPM were assessed. Malignant mesothelial cells, MNML and RL were considered as the gold standard. RESULTS: 189 pleural biopsies with their corresponding cytology specimens were available for review. Among the reviewed cytologies, the diagnoses of 21/189 pleural cytologies were modified. The highest sensitivities were attributed to cytoplasmic blebbing, hypercellularity and cell ball clusters. The most specific feature was the absence of extracellular granular hyaluronic acid cores in reactive cytology and the absence of intercellular openings in NMML cell clusters. Extracellular granular hyaluronic acid cores had the highest positive predictive value and the highest negative predictive value was attributed to the cytoplasmic blebbing in both reactive cytology and NMML. CONCLUSION: These results highlight the fact that no sign is pathognomonic of the diagnosis of MPM pointing out the necessity of immunocytochemical techniques in equivocal cases.

[Thymic hyperplasia: A study of 46 cases]. / Les hyperplasies thymiques.

BACKGROUND: Thymic hyperplasia presents as an anterior mediastinal mass and poses important diagnostic and therapeutic challenge. Two types of thymic hyperplasia are described: true hyperplasia and follicular hyperplasie. Literature data are peculiar concerning both entities. We aimed to describe the clinical and microscopic characteristics of thymic hyperplasia through a single institution experience during an 11-year-period. METHODS: Thymic hyperplasia diagnosed during the period between 2009 and 2020 were included. RESULTS: In all, 46 thymic hyperplasias were diagnosed. The 46 patients consisted in 33 women and 13 men with a mean age of 30 years. Microscopic diagnosis concluded to a follicular hyperplasia in 12 cases and a true thymic hyperplasia in 34 cases. The diagnosis of true thymic hyperplasia posed a diagnostic challenge with an involuted thymus in 1 case and a thymolipoma in 1 case. The confrontation with the clinical data allowed retaining the diagnosis. CONCLUSION: The diagnosis of thymic hyperplasia is based on microscopic features. The confrontation with clinical data and the measurements of the thymus according to the age allow to retain the diagnosis in most challenging cases.